SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a44a090488bac43e8677637f826f5e2f78e23f3685d022ab061894d1ae9dadf' 
  AND token = 'EVq/ppSC4NjusK2pqcC/EHXjwKj72KIMBFGQz/+20aE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}